基于瞬变流计算与安全性分析的大型梯级泵站优化调度研究
发布时间：2018-11-13 12:41
【摘要】：大型梯级泵站一般具有管线长、提水量大、运行时间长、能耗多等特点,不仅在运行调度方面具有较大的优化空间,在机组安全启动和高效运行等方面也具有一定的优化潜力。由于水泵机组运行状态易受振动、机组启动特性、机组启动频繁程度等因素的影响,开展以抽水成本为主要控制目标的优化调度研究,也需要对机组运行可靠性进行分析,并优化机组启动过程,以提高优化调度结果的准确性和可行性。本文基于瞬变流理论和安全性分析,开展大型梯级泵站优化调度研究,为梯级泵站制定合理、经济、可靠的调度运行方案提供了有力的理论依据,具有重要的学术价值和实用价值。 本文综合运用泵站经济运行、流体力学、振动信号分析、非线性转子动力学和智能优化算法等理论,结合水泵运行安全性和可靠性分析,研究大型梯级泵站优化调度问题,具体内容如下： 1.开展优化调度实时性研究：基于明渠／有压管道等非恒定流方程,采用特征线算法求解梯级泵站首站流量变化时全线水力瞬变问题,并与工程调度经验相结合,确定梯级泵站调度运行时各站间流量滞后时差关系,实现优化调度的实时性。 2.针对立式混流泵振动问题,开展水泵运行可靠性对优化调度影响分析：运用HHT方法和转子动力学,从信号分析和数值模拟两方面对叶片全调节立式混流泵异常振动诱因进行研究,并探讨了振动对水泵效率的影响。研究表明,异常振动是由于机组启动时伴生冲击力推动主轴偏移,导致转子不对中运转所引起的,且主轴偏移在机组稳定运行后虽有所减小,但并不会消失；启动伴生冲击力越强越易诱发机组振动,振动越强水泵效率则越低；由于该冲击力是由电机的直接启动方式引起的,改善机组启动方式,降低启动伴生冲击力,不仅可以减弱机组振动,也提高了水泵运行可靠性和优化调度精度。 3.针对机组启动方式改变后启动水锤安全问题以及优化调度所引起的机组频繁启动问题,开展叶片全调节立式混流泵启动参数优化研究：将立式混流泵启动过程分为关阀排气过程和蝶阀开启过程两个阶段,分别采用VOF模型和动网格技术进行三维水锤仿真计算,并利用正交试验法开展电机启动时间、蝶阀开启时间和叶片角度等水泵启动过程参数优化配置研究。研究表明：随着电机启动时间的增加,水泵启动水锤最大值逐渐降低,随着蝶阀开启时间增加,水泵启动水锤最大值逐渐上升,另外,由于叶片角度较小时水泵扬程曲线存在马鞍区,叶片角度应选择-3。。 4.开展单目标优化调度研究：针对大型梯级泵站运行特点,结合系统瞬变流分析和水泵运行可靠性分析成果,建立以系统抽水成本最小为控制目标,以流量分配为决策变量的单目标实时优化调度模型。进而在粒子群算法的基础上,引入免疫思想,开展混合粒子群求解算法研究。实例研究表明：混合粒子群算法增强了粒子活跃性,扩大了解空间的搜索范围,提高了搜索精度,从而增强了粒子群算法避免“早熟”的能力；梯级泵站最优方案比现行的最优调度方案每日节省成本2.99万元,有效的提高了工程经济性。 5.开展双目标优化调度研究：综合考虑抽水成本与机组维修成本等对工程经济性的影响,在假定机组启动次数与机组维修成本呈线性关系的基础上,建立以调度周期内抽水成本最小和机组维修成本最小(机组启动次数最少)为控制目标的双目标实时优化调度模型,并分别采用基于线性加权法的混合粒子群算法和基于Pareto最优解的混合粒子群算法进行求解。研究表明：前者只能获得双目标特定关系下的唯一最优解,当目标权重关系不明时,优化结果可靠性无法确定；而后者则能够反映抽水成本与机组启动次数的内在联系：在日抽水量确定的情况下,随着机组启动次数的增加,抽水成本大致呈现出先减小后增大的趋势,但存在一区域(包含全局最小抽水成本)：随着机组启动次数的变化,抽水成本变化并不明显,该区域即调度方案的最优选择区域。
[Abstract]:The large-scale cascade pump station generally has the characteristics of long pipeline, large water extraction capacity, long running time, and many energy consumption. The large-scale cascade pump station not only has a large optimization space in the operation scheduling, but also has certain optimization potential in the aspects of unit safety start-up and high-efficiency operation. Because the operation state of the water pump unit is easy to be affected by the factors such as vibration, the startup characteristics of the unit and the frequency of the unit startup, the optimal scheduling study based on the pumping cost as the main control target is carried out, the operation reliability of the unit is analyzed, and the startup process of the unit is optimized. so as to improve the accuracy and the feasibility of optimizing the scheduling result. In this paper, based on the transient flow theory and the safety analysis, the optimal scheduling of the large-scale cascade pump station is carried out, and the reasonable, economical and reliable scheduling and operation scheme of the step pump station is provided with a strong theoretical foundation, which is of great academic value and practical value. In this paper, the economic operation, fluid mechanics, vibration signal analysis, non-linear rotor dynamics and intelligent optimization algorithm of the pump station are used in this paper. Combined with the operation safety and reliability analysis of the water pump, the optimal scheduling problem of the large-scale cascade pump station is studied. In this paper, the real-time study of optimization scheduling is carried out: based on the non-constant flow equations such as open channel/ pressure pipe, the hydraulic transient problem of the first station of the step pump station is solved by the characteristic line algorithm, and the problem of hydraulic transient change of the first station of the step pump station is solved by using the characteristic line algorithm, and the problem of the hydraulic transient change of the first station of the cascade pump station is solved by using the characteristic line algorithm. Combined with the experience, it is determined that the time difference of the flow between the stations in the scheduling operation of the cascade pump station is related to the time difference between the stations, and the optimization adjustment is realized. 2. According to the vibration problem of the vertical mixed-flow pump, the influence of the operation reliability of the water pump on the optimal scheduling is carried out: using the HHT method and the rotor dynamics, the abnormal flow-type mixed-flow pump is abnormal in the two aspects of signal analysis and numerical simulation The causes of vibration are studied and the vibration is discussed. The effect of abnormal vibration on the efficiency of the water pump is shown. The study shows that the abnormal vibration is caused by the driving of the main shaft due to the accompanying impact force at the start of the unit, and the deviation of the main shaft is reduced after the stable operation of the unit, but it does not disappear; the stronger the associated impact force is started The more easily the vibration of the unit is induced, the lower the vibration and the stronger the efficiency of the water pump, and as the impact force is caused by the direct starting mode of the motor, the starting mode of the unit is improved, the associated impact force is reduced, the vibration of the unit can be reduced, and the operation of the water pump is improved. 3. To start the problem of water hammer safety after the change of the startup mode of the unit and the frequent start-up of the unit caused by the optimization of the dispatching, and carry out the full adjustment of the blade. The start-up parameter optimization of the mixed-flow pump is as follows: the start-up process of the vertical mixed-flow pump is divided into two stages, namely, the closing valve exhaust process and the butterfly valve opening process, and the three-dimensional water hammer simulation calculation is carried out by adopting the VOF model and the dynamic grid technology respectively, The start-up time of the motor, the opening time of the butterfly valve and the angle of the blade shall be started by the test method. The study of the configuration of dynamic process parameters shows that, with the increase of the starting time of the motor, the maximum water hammer of the water pump is gradually decreased, and the maximum value of the water hammer of the water pump is gradually increased with the increase of the opening time of the butterfly valve. The blade angle should be selected to be-3.. 4. To carry out the single-objective optimization scheduling study: for the operation characteristics of the large-scale cascade pump station, in combination with the transient flow analysis of the system and the analysis of the operation reliability of the water pump, the control target with the minimum pumping cost of the system is established, and the flow distribution is the decision-making. The single objective real-time optimal scheduling model of variable is introduced, and the immune thought is introduced on the basis of the particle swarm optimization algorithm. An example study shows that the hybrid particle swarm algorithm enhances the activity of the particles, expands the searching range of the space, improves the search precision, and enhances the ability of the particle swarm optimization to avoid the 鈥減recocious puberty鈥，
本文编号：2329135
[Abstract]:The large-scale cascade pump station generally has the characteristics of long pipeline, large water extraction capacity, long running time, and many energy consumption. The large-scale cascade pump station not only has a large optimization space in the operation scheduling, but also has certain optimization potential in the aspects of unit safety start-up and high-efficiency operation. Because the operation state of the water pump unit is easy to be affected by the factors such as vibration, the startup characteristics of the unit and the frequency of the unit startup, the optimal scheduling study based on the pumping cost as the main control target is carried out, the operation reliability of the unit is analyzed, and the startup process of the unit is optimized. so as to improve the accuracy and the feasibility of optimizing the scheduling result. In this paper, based on the transient flow theory and the safety analysis, the optimal scheduling of the large-scale cascade pump station is carried out, and the reasonable, economical and reliable scheduling and operation scheme of the step pump station is provided with a strong theoretical foundation, which is of great academic value and practical value. In this paper, the economic operation, fluid mechanics, vibration signal analysis, non-linear rotor dynamics and intelligent optimization algorithm of the pump station are used in this paper. Combined with the operation safety and reliability analysis of the water pump, the optimal scheduling problem of the large-scale cascade pump station is studied. In this paper, the real-time study of optimization scheduling is carried out: based on the non-constant flow equations such as open channel/ pressure pipe, the hydraulic transient problem of the first station of the step pump station is solved by the characteristic line algorithm, and the problem of hydraulic transient change of the first station of the step pump station is solved by using the characteristic line algorithm, and the problem of the hydraulic transient change of the first station of the cascade pump station is solved by using the characteristic line algorithm. Combined with the experience, it is determined that the time difference of the flow between the stations in the scheduling operation of the cascade pump station is related to the time difference between the stations, and the optimization adjustment is realized. 2. According to the vibration problem of the vertical mixed-flow pump, the influence of the operation reliability of the water pump on the optimal scheduling is carried out: using the HHT method and the rotor dynamics, the abnormal flow-type mixed-flow pump is abnormal in the two aspects of signal analysis and numerical simulation The causes of vibration are studied and the vibration is discussed. The effect of abnormal vibration on the efficiency of the water pump is shown. The study shows that the abnormal vibration is caused by the driving of the main shaft due to the accompanying impact force at the start of the unit, and the deviation of the main shaft is reduced after the stable operation of the unit, but it does not disappear; the stronger the associated impact force is started The more easily the vibration of the unit is induced, the lower the vibration and the stronger the efficiency of the water pump, and as the impact force is caused by the direct starting mode of the motor, the starting mode of the unit is improved, the associated impact force is reduced, the vibration of the unit can be reduced, and the operation of the water pump is improved. 3. To start the problem of water hammer safety after the change of the startup mode of the unit and the frequent start-up of the unit caused by the optimization of the dispatching, and carry out the full adjustment of the blade. The start-up parameter optimization of the mixed-flow pump is as follows: the start-up process of the vertical mixed-flow pump is divided into two stages, namely, the closing valve exhaust process and the butterfly valve opening process, and the three-dimensional water hammer simulation calculation is carried out by adopting the VOF model and the dynamic grid technology respectively, The start-up time of the motor, the opening time of the butterfly valve and the angle of the blade shall be started by the test method. The study of the configuration of dynamic process parameters shows that, with the increase of the starting time of the motor, the maximum water hammer of the water pump is gradually decreased, and the maximum value of the water hammer of the water pump is gradually increased with the increase of the opening time of the butterfly valve. The blade angle should be selected to be-3.. 4. To carry out the single-objective optimization scheduling study: for the operation characteristics of the large-scale cascade pump station, in combination with the transient flow analysis of the system and the analysis of the operation reliability of the water pump, the control target with the minimum pumping cost of the system is established, and the flow distribution is the decision-making. The single objective real-time optimal scheduling model of variable is introduced, and the immune thought is introduced on the basis of the particle swarm optimization algorithm. An example study shows that the hybrid particle swarm algorithm enhances the activity of the particles, expands the searching range of the space, improves the search precision, and enhances the ability of the particle swarm optimization to avoid the 鈥減recocious puberty鈥，
本文编号：2329135
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